Example embodiments relate to a calibrator of an optical emission spectroscopy. More particularly, example embodiments relate to a calibrator for calibrating an optical emission spectroscopy that may diagnose plasma state in a plasma chamber.
Generally, a layer may be formed on a semiconductor substrate, and/or a layer on a semiconductor substrate may be etched or cleaned/ashed, using plasma in a plasma chamber of a plasma processing apparatus. Conditions for forming and/or etching and/or cleaning the layer may be determined in accordance with plasma state. Thus, in order to improve productivity of semiconductor devices, the plasma state may be diagnosed using an optical emission spectroscopy (OES). However, an error in the OES may result in inaccurate diagnosis of the plasma state. Thus, calibration of the OES may be required.
After dissembling the OES from the plasma chamber, a reference light may be irradiated to the OES. A spectrum of the reference light may be compared with a spectrum of an actual light inputted into the OES in a plasma process to calibrate the OES.
This calibration of the OES may be possible by disassembling the OES from the plasma chamber, and by transferring the dissembled OES to a calibration apparatus including a reference light source. Further, after calibrating the OES, the OES may be reassembled with the plasma chamber. As a result, a time for calibrating the OES may be long. Furthermore, the OES may be contaminated during the transfer of the OES during calibration.